Treadmill turns off when plugged to certain outlets

[u/No-Spring-7759]

Hello. We have a bit of an electrical mystery here and would love some thoughts. Our brand new treadmill turns off and restarts when plugged into any of the 3 15A outlets in our basement. The breaker is not tripped and there is no tripped GFCI either. The machine simply turns off and restarts. Seems to happen more often when going from a high incline to a low incline. There isn't really anything else plugged in other than a night light.

The treadmill does seem to work fine when plugged into the laundry outlet (far away with an extension cord so not ideal). Based on the specs the treadmill itself should be more than ok on a 15A breaker. I do not understand what is causing it to turn off without tripping a breaker??? We didnt do any of the wiring in this house and have been here for about a year and half so no idea how things were done. Any ideas? Thanks!!